#11467: Panic while type checking expression using function with context holes -------------------------------------+------------------------------------- Reporter: HairyDude | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- {{{#!hs module Bug where holey :: _ => _ holey = undefined useHoley = holey True }}} {{{ $ ghc Bug.hs [1 of 1] Compiling Bug ( Bug.hs, Bug.o ) Bug.hs:3:10: Found hole ‘_’ with inferred constraints: () To use the inferred type, enable PartialTypeSignatures In the type signature for ‘holey’: _ => _ Bug.hs:3:15: Found hole ‘_’ with type: w_1 Where: ‘w_1’ is a rigid type variable bound by the inferred type of holey :: w_1 at Bug.hs:4:1 To use the inferred type, enable PartialTypeSignatures In the type signature for ‘holey’: _ => _ Bug.hs:6:12: Couldn't match expected type ‘Bool -> t0’ with actual type ‘w_’ ‘w_’ is untouchable inside the constraints () bound by the inferred type of useHoley :: t0 at Bug.hs:6:1-21ghc: panic! (the 'impossible' happened) (GHC version 7.10.3 for x86_64-unknown-linux): No skolem info: w__alO[sk] Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.10.3 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11467 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler